allow selecting multiple items at the directories page

app/src/main/java/com/simplemobiletools/gallery/MyRelativeLayout.java

@@ -0,0 +1,46 @@
+package com.simplemobiletools.gallery;
+
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.drawable.Drawable;
+import android.util.AttributeSet;
+import android.widget.RelativeLayout;
+
+public class MyRelativeLayout extends RelativeLayout {
+    private Drawable mForegroundSelector;
+
+    public MyRelativeLayout(Context context) {
+        super(context);
+    }
+
+    public MyRelativeLayout(Context context, AttributeSet attrs) {
+        super(context, attrs);
+    }
+
+    public MyRelativeLayout(Context context, AttributeSet attrs, int defStyleAttr) {
+        super(context, attrs, defStyleAttr);
+    }
+
+    {
+        mForegroundSelector = getResources().getDrawable(R.drawable.selector);
+    }
+
+    @Override
+    protected void drawableStateChanged() {
+        super.drawableStateChanged();
+        mForegroundSelector.setState(getDrawableState());
+        invalidate();
+    }
+
+    @Override
+    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
+        super.onSizeChanged(w, h, oldw, oldh);
+        mForegroundSelector.setBounds(0, 0, w, h);
+    }
+
+    @Override
+    protected void dispatchDraw(Canvas canvas) {
+        super.dispatchDraw(canvas);
+        mForegroundSelector.draw(canvas);
+    }
+}

app/src/main/java/com/simplemobiletools/gallery/activities/MainActivity.java

@@ -4,15 +4,19 @@ import android.Manifest;
 import android.content.Intent;
 import android.content.pm.PackageManager;
 import android.database.Cursor;
+import android.media.MediaScannerConnection;
 import android.net.Uri;
 import android.os.Bundle;
 import android.provider.MediaStore;
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.content.ContextCompat;
 import android.support.v7.app.AppCompatActivity;
+import android.view.ActionMode;
+import android.view.Menu;
+import android.view.MenuInflater;
+import android.view.MenuItem;
 import android.view.View;
 import android.widget.AdapterView;
-import android.widget.AdapterView.OnItemClickListener;
 import android.widget.GridView;
 import android.widget.Toast;
 
@@ -28,9 +32,12 @@ import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
-public class MainActivity extends AppCompatActivity implements OnItemClickListener {
+public class MainActivity extends AppCompatActivity
+        implements AdapterView.OnItemClickListener, GridView.MultiChoiceModeListener, MediaScannerConnection.OnScanCompletedListener {
     private final int STORAGE_PERMISSION = 1;
     private List<Directory> dirs;
+    private GridView gridView;
+    private int selectedItemsCnt;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -69,9 +76,10 @@ public class MainActivity extends AppCompatActivity implements OnItemClickListen
         dirs = new ArrayList<>(getDirectories().values());
         final DirectoryAdapter adapter = new DirectoryAdapter(this, dirs);
 
-        final GridView gridView = (GridView) findViewById(R.id.directories_grid);
+        gridView = (GridView) findViewById(R.id.directories_grid);
         gridView.setAdapter(adapter);
         gridView.setOnItemClickListener(this);
+        gridView.setMultiChoiceModeListener(this);
     }
 
     private Map<String, Directory> getDirectories() {
@@ -109,4 +117,44 @@ public class MainActivity extends AppCompatActivity implements OnItemClickListen
         intent.putExtra(Constants.DIRECTORY, dirs.get(position).getPath());
         startActivity(intent);
     }
+
+    @Override
+    public void onItemCheckedStateChanged(ActionMode mode, int position, long id, boolean checked) {
+        if (checked)
+            selectedItemsCnt++;
+        else
+            selectedItemsCnt--;
+
+        if (selectedItemsCnt > 0)
+            mode.setTitle(String.valueOf(selectedItemsCnt));
+
+        mode.invalidate();
+    }
+
+    @Override
+    public boolean onCreateActionMode(ActionMode mode, Menu menu) {
+        final MenuInflater inflater = mode.getMenuInflater();
+        inflater.inflate(R.menu.directories_menu, menu);
+        return true;
+    }
+
+    @Override
+    public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
+        return false;
+    }
+
+    @Override
+    public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
+        return false;
+    }
+
+    @Override
+    public void onDestroyActionMode(ActionMode mode) {
+        selectedItemsCnt = 0;
+    }
+
+    @Override
+    public void onScanCompleted(String path, Uri uri) {
+
+    }
 }

app/src/main/java/com/simplemobiletools/gallery/activities/PhotosActivity.java

@@ -44,7 +44,6 @@ public class PhotosActivity extends AppCompatActivity
     private int selectedItemsCnt;
     private GridView gridView;
     private String path;
-    private PhotosAdapter adapter;
     private Snackbar snackbar;
     private boolean isSnackbarShown;
     private List<String> toBeDeleted;
@@ -95,7 +94,7 @@ public class PhotosActivity extends AppCompatActivity
         if (isDirEmpty())
             return;
 
-        adapter = new PhotosAdapter(this, photos);
+        final PhotosAdapter adapter = new PhotosAdapter(this, photos);
         gridView = (GridView) findViewById(R.id.photos_grid);
         gridView.setAdapter(adapter);
         gridView.setOnItemClickListener(this);
@@ -207,6 +206,7 @@ public class PhotosActivity extends AppCompatActivity
 
     private void updateGridView() {
         if (!isDirEmpty()) {
+            final PhotosAdapter adapter = (PhotosAdapter) gridView.getAdapter();
             adapter.updateItems(photos);
         }
     }
@@ -234,7 +234,7 @@ public class PhotosActivity extends AppCompatActivity
     @Override
     public boolean onCreateActionMode(ActionMode mode, Menu menu) {
         final MenuInflater inflater = mode.getMenuInflater();
-        inflater.inflate(R.menu.cab, menu);
+        inflater.inflate(R.menu.photos_menu, menu);
         return true;
     }
 

app/src/main/java/com/simplemobiletools/gallery/adapters/DirectoryAdapter.java

@@ -9,12 +9,11 @@ import android.widget.ImageView;
 import android.widget.TextView;
 
 import com.bumptech.glide.Glide;
-
-import java.util.List;
-
 import com.simplemobiletools.gallery.Directory;
 import com.simplemobiletools.gallery.R;
 
+import java.util.List;
+
 public class DirectoryAdapter extends BaseAdapter {
     private final Context context;
     private final List<Directory> dirs;
@@ -40,7 +39,7 @@ public class DirectoryAdapter extends BaseAdapter {
         Directory dir = dirs.get(position);
         holder.dirName.setText(dir.getName());
         holder.photoCnt.setText(String.valueOf(dir.getPhotoCnt()));
-        Glide.with(context).load(dir.getThumbnail()).centerCrop().crossFade().into(holder.dirThumbnail);
+        Glide.with(context).load(dir.getThumbnail()).placeholder(R.color.tmb_background).centerCrop().crossFade().into(holder.dirThumbnail);
 
         return view;
     }

app/src/main/res/layout/activity_main.xml

@@ -5,6 +5,7 @@
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:background="@android:color/black"
+    android:choiceMode="multipleChoiceModal"
     android:columnWidth="@dimen/dir_tmb_size"
     android:horizontalSpacing="1dp"
     android:numColumns="auto_fit"

app/src/main/res/layout/directory_item.xml

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
-<RelativeLayout
+<com.simplemobiletools.gallery.MyRelativeLayout
     xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="@color/tmb_background">
+    android:foreground="@drawable/selector">
 
     <com.simplemobiletools.gallery.MyImageView
         android:id="@+id/dir_thumbnail"
@@ -35,4 +35,4 @@
             android:textColor="@android:color/white"/>
 
     </RelativeLayout>
-</RelativeLayout>
+</com.simplemobiletools.gallery.MyRelativeLayout>

app/src/main/res/menu/photos_menu.xml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+      xmlns:app="http://schemas.android.com/apk/res-auto">
+    <item
+        android:id="@+id/cab_remove"
+        android:icon="@android:drawable/ic_menu_delete"
+        android:title="@string/remove"
+        app:showAsAction="always"/>
+</menu>